Salaam
Yes she can feed her child in the state of Janabah. It is recommended to do wudhu before feeding.
Dr Masuma Jaffer is a qualified dentist, with a Masters in Islamic Studies and has also attended Hawza in Qum. She obtained a PGCE - teaching qualification – and has taught Hawza studies at the Islamic College in London. She also has a Diploma in Counselling and is a Qualified Chaplain and worked with women prisoners at Holloway and with Hertfordshire Police advising them on Muslim matters.